Process of obtaining beryllium and aluminum compounds



Sept. 15, 1931.

emo exmcnao 8 S 945:0 EXTRACTEO 8 8 c. B. SAWYER ET AL 1,823,864

PROCESS OF OBTAINING BERYLLIUM AND ALUMINUM COMPOUNDS Filed Oct. 14,1930 EXTRACTION OF BEO H204 HEAT TREATED NEW HAMPSHIQE BEIZYL EXTRACTIONOF 850 men RAW smYLmEw WITH SULPHUHIC ACID CF loo Au. SAMDLES QAPIOL'!AIR cameo VARIOUS CONCENTRATIONS EXTBACTIONS mos wrrn sa'ae. qo

suumumc m0 AT 236' 0. FOR 15! nouns.

70 a E 50 3 5 W 50 o I]; a 40 3 250 260 TEMPERATURE OF ACID TREATMENTFIG. 5

0 Z 4 6 B IO I2 rm: OF HEAT TREATMENT won: (nouns) FIG. 1

seo EXTIZACTED mom 552w. (NEW HAMPSHIRE) 46}; suwnumc ACID AT 25m #041 mnouas (mzzssua: TREATMENT) 6. 3. BY 64x 2 W ATTOQNEY an" 500' 100 300q00 TEMPERATUQE OF 025 TREATMENT FIG. 2

Patented Sept. 15, 1931 UNITED STATES PATENT ol-"rlcs CHARLES B. SAWYERAND B ENGT KJELLGBEN, OI CLEVELAND, OHIO, ASBIGNORS TO THE BRUSHBERYLL'IUM COMPANY, OF OLEVELAHD, OHIO, A CORPORATION O]? OHIO PROCESSOF OBTAINING IBERYLLIUM AND ALUMINUM COMPOUNDS Application filed October14, 1930, aerial No; 488,662, and in Canada January 6, 1921.

I have filed applications for this patent in Ca'In'ada, Serial No.320,889, Jan. 6, 1927, and in Germany, Serial No. 129,473, J an. 31,1927.

This invention relates to a process for the extraction of beryllium anduminum from ores containing them, such as beryl.

Heretoforethere has been no satisfactory method of recovering berylliumfrom the ore beryl because of the latters extremely high resistance tothe action of most reagents. a One object of this invention is to rovidea method of treating beryl to make it more susce tible to the action ofsuitable reagents. A urther ob 'ect of the invention is to provide arelative y simple and cheap process for converting the beryllium andaluminum naturally occurring in the ore into soluble beryllium andaluminum salts from which the corres onding oxides may be formed.

Other oh'ects of the invention will be a (parent to t ose skilled in theart from t e escription of it hereinafter given.

In describing our process, reference will be made to the accompanyingdrawings which illustrate certain features of the process.

In the drawings, Fig. 1 is a series of curves showing the 'eifect ofheat treatment of beryl at various temperatures uponiacid recoverytreatment at approximately atmospheric pressure. p y

Fig. 2 is a curve and data showing the effect of heat treatment of berylat various temperatures upon acid recovery treatment above atmosphericpressure.

Fig. 3 is a series of curves showing the effect of treatment underpressure of raw beryl with sulphuric acid of various concen- 40 trationsat various temperatures (pressures).

Our invention is based pnmarily on the discovery that beryllium andaluminum occurring in beryl may be made susoe tible to the action ofsuitable reagents by su jecting the beryl to the action of heat in amanner to modify its physical structure and so render it more readilyattacked by the reagent to be used.

The heat treatment of the beryl can be carried out at varioustemperatures. The

resulting modification of the ore begins at temperatures below 1000 C.and increases as the temperature of the treatment is increased. However,the increase in the effect of the treatment with increasein thetemperature of the treatment is relatively slow below 1000 C. andbecomes more rapid at temperatures above 1000 C; The maximum effect issecured by heating the ore to melting, at temperatures normally 9 from1500 to 1600 0., and suchtreatment renders the ore readily attackable bysulphuric acid. However, when the beryl is heated at the more moderatetemperature of sintering, such as about 1350 (1., and at still lowertemperatures it is sufficiently modified. so that it is attached bycertain reagents, such as sulphuric acid, althou h if the heat treatmentof the ore is carri out at temperatures below its meltin point thetreatment must be continued or a longer time than when the beryl iscompletely melted and also it may be necessary to treat the ore at ahigher temperature with the reagent if the ore has not been heated tothe point of is com lete melting. T e modification of the ore due toheating is not so pronounced if the ore is allowed to cool very slowly.Therefore, both as a matter of convenience and to ,secure the maximumefi'ect of the treatment, we re. idly cool the heated ore preferably byquenc ing i in a suitable medium, such as water. This es the ore in itsmodified state. It is possible to cool the ore in air fairly rapidl butin order to secure a maximum rate 0 .cooling we prefer to use a liquidquenching medium. The maximum reactivity of the ore is secured byquenching it from the molten state. The effect of quenching upon thereactivity is less 0 if the ore is heat treated at lower temperatures.We have found-that beryl may be heated as for example, in a recupefatlveoil fired furnace, or in an electric furnace, above the r fusion pointso that it forms a free flowing molten liquid and, therefore, the heatincan be carried out if desired in a furnace 0 such character that themolten beryl will continuously run out directly into a quenching me- 199dium such as water. Or if preferred, the beryl can be melted in afurnace and poured at intervals into the quenching medium.

After modification of the beryl by any-of the above methods, the berylmay be treated with a suitable reagent to attac the beryllium andaluminum content of the beryl. While it is possible to use hydrochloricacid, nitric acid, an aqueous solution of sodium hydroxide or otherbases, and other reagents, to extract the aluminum and beryllium inberyl that has been modified by our improved process, we prefer toemploy one of the mineral acids, and especially sulphuric acid, as thereagent.

To facilitate the reaction between the beryl and the reagent selected,said modified beryl can be comminuted, as in a suitable grinding mill.The said reagent is preferabl one which will render the aluminum andllium content of the beryl soluble, but which will leave the silicacontent thereof in insoluble condition. The said reagent may be mixedwith said be:- 1 and heated to a tem- Eerature sufliciently igh and fora time sufciently long to render said aluminum and beryllium soluble, asby the conversion thereof to soluble salts.

It may be noted that in general the more complete the modification ofthe beryl, the greater is the reactivity thereof. Thus, the strength ofreagent and the time and temperature required for the reaction betweenthe beg:i and reagent varies with the degree of mo cation of the beryl,which in turn varies, within limits, with-the temperature to which theberyl has been heated, the length of heating and the rapidity of thecooling of said he if it is desired to specially cool the beryl. n thisconnection, it may be noted that the density of the beryl appears to bean indication of the degree 0 modification thereof. Thus the morecomplete the modification of the beryl, the lower appears to be thedensity thereof. For example, the density of one grade of crude berylhas been found to be 2.69, and be 1 that has been melted but notquenched as a density of 2.57. Beryl melted in a pot and poured intowater was found to have a density of 2.49, while the beryl melted in afurnace and run constantly over a hot lip into water had a still lowerdensity of 2.46.

As above indicated, we have found that sulphuric acid, preferablysomewhat diluted, such as concentrations between 46 to 63 degrees Baumis a suitable rea eat to render soluble the aluminum and/0r rylliumcontent of be rl. Thus, for example sulphuric acid may mixed withmodified beryl to an amount slightly greater than that theoreticallyrequired to react with the aluminum and beryllium and the mixtureheatedin a suitable vessel, such as, for example, an open lead pot or even aniron pot. Thus for example, we have found that the reaction be tween themodified beryl and sulphuric acid may be substantially completed byheating for a relatively short time, such as an hour or less atsubstantially atmospheric pressure. It will be understood that thereaction between the beryl and sulphuric acid may be carried out byheating the reaction mixture for longer or shorter times, do udin inpart upon the temperature emp oyed. TVe have'discovered that thetemperature and pressure at which the treatment of the modified ore withthe acid or other rea at is carried out are important factors a actingthe degree of extraction of the beryllium and aluminum contents of theore. Indeed the effect of increasin sure in treating the ore withsulphuric acid, for example, is so marked that the treatment underpressure may under some conditions be a major consideration in thepractice of our process. Furthermore, we have found that theincreasedactivit secured by treatment under pressure holds true in the case ofraw or unheated beryl as well as in the case of heat treated ore.Treatment of the ore under pressure can be carried out with thetemperature and pressulphuric acid, for example, in a closed tubeor, ona larger scale, in a lead lined autoclave or other suitable container.At a later point in the description we shall refer further to thetreatment under pressure in connection with the drawings.

By taking advantage of the differential reactivities of the berylliumand aluminum compounds as existing in the modified beryl and of thevarious factors affecting the activit of the sul huric acid inconverting the bery 'um and a uminum compounds of such her I intosoluble sulphates, the beryllium and aluminum may either be extractedsuccessively or simultaneously, as desired. For example, if a meltedberyl, such as is found in South Dakota, is treated with sulphuric acidof about the concentration of chamber acid and at a temperature of about200 (3., a good extraction of the her llium from the treated beryl isobtained. ith the said acid at a higher temperature, such as 250 C. forinstance, the aluminum is also attacked, and it will thus be seen thatvariation of the temperature afi'ords a method for the separateextraction of the beryllium and aluminum contained in the ori 'nalberyl. Beryls from other deposits may ave both the beryllium content andaluminum content rendered soluble even by the first of these twotreatments and therefore the amount of action or the activity of theacid in attacking the beryllium and aluminum compounds of the beryl willhave to be diminished if it be desired to extract the beryllium andaluminum successively, as will be more fully explained. And beryls fromstill other deposits, on the other hand, may need to have the activityof habits the acid increased, de ending upon the composition of theberyThe ber 11mm and aluminum mayeitherbe extracte successifvely orsimultaneously, as desired, depending upon the degree of modification ofthe beryl, the concentration of the acid used and t e tem rature andtime of reaction between the aci and the comminuted beryl.

When the beryllium and aluminum contents of the beryl are attacked toform the soluble aluminum and beryllium sulphates, the silica is left asa silicic acid completely dehydrated if the temperature of treatment issufliciently high.

The product of the reaction between the beryl and a suitablereagent,such as, for example, sulphuric acid, may be treated with water or otherliquid, the soluble aluminum and beryllium com unds dissolved therein,the solutiomfiltered to remove insoluble ma-: terial andjxthe aluminumand beryllium compounds recovered from such filtrate, by methodshereinafter described.

Dependent on the composition of the natural beryl, there may be alsoconsiderable quantities of iron sulphate in the sulphate solution. Afterremovin the aluminum and beryllium, a final mother 'quor with the ironcontent therein remains.

In carrying out our process, after treatment of the modified beryl withsulphuric I acid we prefer to extract'the sul hates with water from thesulphated material so as to make an aqueous solution of the sulphates.From this solution the aluminum sulphate maybe completely separated byconverting it into an alum, for example, ammonia alum, by adding asuflicient amount of ammonium sulphate, and subsequently remoying thealum by crystallization. It has been known that a major portion of thealuminum can be separated from the other sulphates as an alum, butheretofore it has never been possible to secure a complete separation.According to the present invention a complete separation may be attained'by eitherof two methods,

both of which are based on the discovery that an alum, such for exampleas ammonia alum or potassium alum, is substantially insoluble in anaqueous solution, of suitable concentration and temperature, containinga mixture of bezllium sulphate and an alkali sulphate, sue for exampleas ammonium sulphate or potassium sulphate.

A saturated solution of beryllium sulphate dissolves some ammonia aluinat room ternperature. If, however, ammonium sulphate is added thesolubilit of ammonia alum in this solution rapidly ecreases and ispractically zero at about 18 (3., when the amount of ammonium sul hate aproaches about 6% L of the wei ht 0 cr stalllne beryllium sul phate inso ution. I the beryllium sulphate solution is not saturated a greateramount of ammonium sulphate has to be added. Also if the temperature ofthe beryllium sulphate solution is increased, more ammonium sulphate hasto be added. For practical purposes it is preferable to use an amount ofammonium sulphate equal to 10-20% of the weight of the crystallineberyllium sulphate present in order to secure a wider usable ran e ofconcentrations and temperatures.

fiery high percenta es of ammonium sulphate can also be used, but it is,of course, preferable to use as little ammonium sulphate as practicallypossible. If the amount of ammonium sul hate is less than about 6% ofthe weight 0 the crystalline beryllium sulphate the alummay still becompletely separated by cooling the solution to temperatures lower thanordinary room temperatures.

One of the two separation methods referred to consists in separating thealum by adding to the sulphate solution obtained by leaching thesulphatized ore an excess of ammonium sulphate whereby the ammonia alumformed becomes substantially insoluble in the solution and the berylliumsulphate remains entirely soluble. The excess of ammonium sul phate useddepends to some degree on the concentration of the sulphate solution. Inorder entirely to remove all the ammonia alum, it is preferable to carryout the crystallization in'such a way that also some beryllium sulphateis or stallized out together with the ammonia alum. After separating theammonia alum by filtration or otherwise, the beryllium sulphate contentof the alum may be washed out and the washngs returned to the aqueoussulphate solution obtained from the leaching of the ore. The

mother liquor obtained after separatin the alum contains practically allthe bery ium sulphate together with the iron content of the ore. Byevaporation and crystallization of the beryllium sulphate from thismother liquor most of the iron is left in the mother liquor and acrystalline beryllium sulphate containing very little iron obtained.

The other method of separating the alum consists in adding to thesulphate solution obtained by leaching the sulphated ore enough ammoniumsulphate to form ammon'a alum and then crystallizing out berylliumsulphate and ammonia alum together. After separation of the mixedcrystals these crystals are leached with a suitable solution containingberyllium sulphate and ammonium sulphate. Such a leaching solution maycontain, for example, 250 ams of crystalline beryllium sulphate perliter anl fiO g'rams of ammonium sulphate per liter. A solution of thisconcentration is capable of extracting about 570 grams of berylliumsulphate per liter at 20 C. from a mixture of beryllium sulphate andalum without dissolving the alum. The leaching process is carried out bystirring the mixed crystals preferably at room temperature or lowertemperatures with the leaching solution. By this treatment all of theberyllium sulphate crystals are dissolved and the ammonia alum crystalsleft. The ammonia alum is further separated from the solution byfiltration or otherwise and the beryllium sulphate in the filtraterecovered by evaporation and crystallization. The remainingmother 1i uorcontaining ammonium and beryllium su phates ma then be used a ain forleaching purposes a ter proper dilution with water.

a It will be s'een that whichever of the two procedures for separatingthe alum is used there is involved essentially the use of a solution ofberyllium sulphate and an alkali sulphate which contains an amount ofthe alkali sulphate suflicient to render the alum completely insolublein the solution of the concentration and temperature employed.

In each of the above described methods of separating the aluminumcontent the beryllium suiplhate formed generally contains some iron.

is beryllium sulphate is purified by recrystallization.

In all of the crystallizing operations herein described in which iron ispresent it should preferably be in the ferrous state and suchcondition-can be insured b any ,well known method, such as the intronotion of sulphur dioxide or barium sulphide.

The iron which remains in the mother liq uor obtained from thecrystallization of b ryllium sulphate in the first described method ofseparating the aluminum content -or from the crystallization'of themixed crystale of beryllium sul hate and ammona alum in the second methomay be lar ely removed therefrom in any one of severa ways, such as, forexample by further concentrationof the solution and .crystallizing outof ferrous ammonium sulphate. The final mother liquor remaining from theiron crystallization contains substantially all the excess free acid andis sufliciently reduced in iron content to permit its use as a reagentfor subsequent treatment of additional beryl, or it may be added to thesulphate solution obtained by leaching the sulphatizedore;

If the sulphate solution obtained by leaching the ore contains much freeacid, ammonia may be added instead of ammonium sulphate. It will thus beseen that by the use of ammonia the excess sulphuric acid may berecovered as ammonium sulphate and thereby utilined in the process forthe formation of ammonia alum. 1

The beryllium sulphate produced by our above described method can bedecomposed into sulphur trioxide and beryllium oxide by heating totemperatures such as 800 to 1000 C. The sulphur trioxide may beconverted to sulphuric acid for use in the process. Also the ammoniaalum roduced 1n the process me. be decomposed into ammonium sulphate analuminum sulphate, for example, by the ammonia alum bemg recovered. Thealuininum sulphate produced in this'manner may in turn e decomposed intoaluminum oxide and sulphur trioxide in the same manner as the berylliumsulphate. If desired, the mixed crystals of beryllium sulphate andammonia alum may be converted into the mixed oxides of her llium andaluminum.

An indicative of the modification of beryl by our method of heattreating the same, we have shown in Fig. 1 of the drawing a series ofcurves indicating the effect of the heat treatment of the beryl upon therecovery of the beryllium content by our method of treatment. theberyllium content, in terms of the percent of beryllium oxide extracted,is plotted vertically against the time of the heat treatment of theberyl, the curves representing heat treatments at the difierenttemperatures. The extractions of the modified beryl were made with 100%excess of 63 B6. sulphuric acid at 236 C. in a closed tube, the time ofthe acid treatment in each case being 15 hours. i

It will be observed onreferring to the curves that for this particularacid treatment the effect of heat treatment at 1000 C. u on thereactivity of the beryl was measurable ut relatively small. The eflectof the heat treatment at 1200 C. is still reater but the increase isnot'marked. owever, when the heat treatment of the beryl is carried outat 1300 C. the recovery of the beryllium con:

tent is markedly increased, being nearly It will be noted that therecovery of p in turn is fully double that for the treatment at 1300 C.The data for the treatment at 15.00" C. is not so full but it will benoted that the increasein the recovery for the treatment at 1500 C. ismarkedly reater than that for 1400 (1.; and, finally, w en the ore washeated to the melting point and rapidly cooled in air the recoverywas'increased to about eighty percent. By quenchin' the melted ore inwater we have been ab e to attain a beryllium recovery of nearly 99%.

In Fig. 20f the drawings we resent data which indicate the efi'cct both0 acid treatment under pressure andoi the heat treatment of the ore.This figure represents treatment of heat treated beryl with 46 B6.sulphuric acid at 251 C. (approximately 118 C. above the boilingpoint'of the acid) for 19'hours, and the percent of beryllium oxideextracted is plotted "vertically against a-one-hour heat treatment *ofthe ore at various temperatures. On comparing Fig. 2 with Fig. 1 it willbe observed that the effect of the acid treatment of the are underpressure is to verysubstantially increase the extraction of berylliumoxide both from the raw ore and the heat treated ore. Even in the caseof the raw ore the extraction is increased by the use of pressure from avery few percent to upwards of 50%. Also, it will be seen from acomparison of these two figures that the increase in the recovery ofberyllium oxide from the ore incident to the increase in the temperatureof the ore treatment is even more marked when the acid treatment iscarried out under substantial pressure than when it is carried out atatmospheric pressure. From Fig. 2 it will be noted that a heat treatmentof the ore as low as 935 gives the relatively high extraction ofberyllium oxide of 76+ if the heat treatment of the ore is suflicientlyprolonged, thus bringing out the influence of the time of heat treatmentof the ore.

Considering both Figs. 1 and 2, it will be seen, as we pointed outearlier in the description, that while the heat treatment of the ore attemperatures below 1000 C. somewhat increases the reactivity of the ore,the rate of increase of the reactivity with increase of temperature upto about 1000 C. is relatively slight while heat treatment of the ore attemperatures above about 1000 C. increases its reactivity more and morerapidly up to the maximum efi'ect which is secured at the meltingtemperature of the ore.

Fig. 3 of the drawing is a series of curves representing extraction ofberyllium oxide from raw beryl by 17 hours treatment with sulphuric acidof various concentrations at various temperatures above the boilingpoint of the acid, the treatments being carried out in a closedcontainer. The extraction of beryllium oxide is plotted verticallyagainst the temperature of the acid treatment and each curve representsa particular acid concentration. This series of curves shows that theberyllium oxide extraction increases with decrease in the concentrationof the acid and with increase in the temperature of the acid treatment,both of which factors correspond to increase in the pressure. The datain this figure also shows the effect of the time factor in the acidtreatment, the extraction of beryllium oxide by 46 B. acid at 265 C.being increased from about 66% to about 76% by prolonging the acidtreatment from 17 hours to 46 hours.

The beryl found in diiferent deposits varies somewhat in composition andwe have found that the differences in the composition of the ore causeit to behave somwhat diflerentlv in the application of our improvedmethod. Our study of ores of different composition has resulted in thediscovery that it is possible, in the case at least of some of the ores,to improve their adaptability to our process by the addition to them ofsuitable substances. In particular, we have found that by the additionto the beryl of suitable substances in very small amounts it ispossible, without interfering with the successful carrying out of thevarious steps of our process, to ver substantially lower the meltlngpoint of t e ore and thus permit a modification of the ore b ourimproved heat treatment at a markedly ower temperature than wouldotherwise be possible, thus realizing substantial economic gains in theprocess.

Furthermore, we have found that by the addition of a suitable substanceor substances it is possible to not only thus lower the melting point ofthe ore but also to increase the reactivity of the ore, in a mannerwhich we do not fully understand but which we believe essentiallyinvolves a retardation of the recrystallization of the melted ore.

Among the substances which may be added to the ore for the purposesspecified are compounds oxides for example, of iron, calcium and sodium.All of these substances when added to the ore in smallamounts have theeffect of lowering its melting point and iron, for example, also has themarked added effect of increasing the reactivity of the ore when meltedand quenched, this latter effect being due, we believe to a retardingefl'ect upon the recrystallization of the melted ore, thus insuring thepreservation to a higher degree of the modifying eflect of the heattreatment. The addition to the ore of any one or more of the substancesabove mentioned obviously will not interfere with any of the severalsteps of our rocess of treatment. Two of the ores whic we have used onefrom New Ham shire and the other from South Dakota, will serve toillustrate the efl'ect of the composition of the ore which we have justbeen de- Of these two ores, that from South Dakota was found to have alower melting point than that from New Hampshire but the latter ore, onthe other hand, after melting and rapid cooling was found to have ahigher reactiv1ty to the acid treatment. By the addition of a smallamount of iron oxide to the South Dakota ore we found it possible toincrease its reactivity to the acid treatment, as well as somewhatfurther lowering its melting point, thus illustrating the efl'ect ofmodifying the composition as above described.

As illustratin the character of our process we give the 0 owing specificexample, in which sulphuric acid is employed as reagent:

100 lbs. of beryl, which has been melted and quenched as above explainedand ground to pass a Tyler 200-mesh sieve, is mixed with 120 lbs. 63 B.sulphuric acid, which is about 10% excess of the acid. The mixture isthen heated in an iron container. As soon as the acid becomes slightlywarm the reaction starts, and the temperature increases rapidly. Steamand gases go ofi, and the mixture seems to boil. After about hour thereaction slows down. The container is then covered and heated up to250300 C. for about 24 hours, to dehydrate the silica formed. Aftercooling, the white sulphated material is broken up in lumps and leachedwith water. The insoluble residue is separated by filtration and thefiltrate concentrated to a specific gravity of about 1.32 at 20 C.

The filtrate or solution now has a volume of about 117 liters, andcontains about:

35 grams BeO per liter 49 A1 0 per liter 3 F8203 per liter in the formof sulphates.

The extracted yield of beryllium oxide is about 90%.

In order to separate the aluminum from the beryllium, ammonium sulphateis added to the solution, and ammonia alum separated by crystallization.The solution above contains 5740 grams A1 0 as aluminum sulphate. Itwould require 7400 grams ammonium sulphate to form ammonia alum.However, about 25% excess ammonium sulphate. or 9400 grams, is used. Itmay be dissolved in waterto a saturated solution and added directly tothe cold sulphate solution. The ammonia alum crystallizes quickly and isseparated by filtration. The mother liquor has a volume of about 104liters and a specific gravity of about 1.21 at 15 C.

It contains about:

33 grams BeO per liter .32 ALO, 2.9 c Z :c 19 i free (NHQ SO, per liter.

The acidity of the solution is 1.5 to 2.0 normal in sulphuric acid.

For removal of the last part of the aluminum present. this mother liquoris concentrated to a specific gravity of 1.32 at boiling temperature, orto a volume of about 60 liters, and then crystallized by cooling to roomtemperature. The crystals consisting of ammonia alum and some berylliumsulphate are separated by filtration. The filtrate is now free fromaluminum according to test carried out by the 8-hydroxyquinolineseparation method by Berg, as modified by Kolthotl' and Sandell(JournalAmerican Cbimical So ciety. 50, 1900 (1929) It has a specificgravity of about 1.30 at 20 C. and contains about:

73 grams BeO per liter and 10 F os i in the form of sulphates.

For separation of the beryllium from the iron the filtrate isconcentrated to about 1.45- 1.46 specific gravity at boilingtemperature,

nausea and the solution crystallized by cooling, hav ing preferablyfirst reduced the iron with sulphur dioxide. The crystals formed contain01% of Fe O By recrystallization of the beryllium sulphate formed theiron content of the crystals is only .002 to 003%. In other words, theberyllium sulphate is practically chemically pure.

It will be understood that the beryllium sulphate produced canbe treatedin various known ways to convert the beryllium content to differentforms. For example, the sulphate can be converted to beryllium oxide byheating it to drive off sulphur trioxide; and the beryllium oxide, inturn, can be converted into various other compounds such as fluoridesand chlorides suitable for electrolysis.

As further illustrating the practice of our improved process, We givethe following example using hydrochloric acid as reagent:

A suitable amount of beryl modified, as previously explained, by meltingquenching and ground to pass a ZOO-mesh sieve. is mixed withconcentrated hydrochloric acid largely in excess of the amounttheoretically necessary to react with the silicates of the ore. WVe havefound that an excess of 100% is suitable which is equivalent to a ratioof 4 cc. of the concentrated acid to one gram of beryl like that of thefirst example above given. i

The mixed beryl and acid when heated react to form a solution ofberyllium, alumiumn and iron chlorides and with the heating conducted at84 C. for about 19 hours the yield of beryllium chloride isapproximately 66% and of the aluminum and iron chlorides combinedapproximately 67%.

The separation of the chlorides is effected by treatment of the solutionin known ways. For example, the solution can be treated withhydrochloride acid gas at low temperatures to effect separation of thechlorides, as described by Gooeh in his Methods in Chemical Analysis,first edition, pages 214 to 216.

It is recognized that it is known to heat beryl with oxides of alkalisand alkaline earths and with magnesium oxide in order to decompose theberyl and render the formed materials soluble in sulphuric acid. It isalso known to sinter or use aluminum silicates containing considerableamounts of alkalis, such as feldspar, in order to render them soluble insulphuric acid. Furthermore, it is known to heat aluminum ores. such asclay, to temperatures below 900 C. to ren der.them more reactive tosulphuric acid. However, the present process is distinguished in thatthe heat treatment increases the reactivity of the beryl to reagents,such as sulphuric acid, by effecting a change in the physical structureof the ore and Without any substantial change in its chemicalcomposition, and in that this increase in reactivity is secured in anore which contains no and i significant amount of alkalis. The result,in the present process, is to make the ore beryl, heretofore consideredhighly resistant, subject to direct attack by reagents, such assulphuric acid, which would not attack the nat ural beryl.

The present application constitutes a con tinuation in partof ourearlier filed applications Serial No. 5169, filed January 27, 1925, andSerial No. 123,593, filed July 19, 1926. In the present application wedo not claim the hereindisclosed method of treating the beryl with areagent under superatmospheric pressure nor the addition of an oxide tothe beryl to facilitate the modification thereof nor the methods ofrecovering the beryllium and aluminum from the ore after it has beentreated with sulphuric acid or other reagent, these several methods orfeatures and certain features incidental thereto being claimed in ourcopcnding application Serial No. 536,518, filed May 11, 1931, as adivision of the present application.

To those skilled in the art it will be apparcut that our invention canbe practiced with a variety of modifications and in various differingembodiments without departing from the spirit and scope thereof asdefined in the appended claims.

What we claim is:

1. The process of extracting beryllium from beryl which comprisesmodifying the physical structure of the beryl by heating it at atemperature above 1000 C. and thereby increaslng its reactivity withoutthe necessity of addition of reagents, and thereafter treating themodified beryl with a reagent adap ed to transform its beryllium contentinto a soluble form.

2. The process of extracting beryllium from beryl which comprisesmodifying the physical structure of the beryl by heating it at atemperature above 1000 C. and thereby increasing its reactivity withoutthe necessity of addition of reagents, and thereafter treating themodified beryl with a mineral acid 0 a temperature and a concentrationadapted to trans 'rm its beryllium content into a soluble form.

3. The process of extracting beryllium from beryl which comprisesmodifying the physical structure of the beryl by heating it at atemperature above 1000 C. and thereby increasing its reactivity withoutthe necessity of addition of reagents, and thereafter treating themodified beryl with sulphuric acid of a. temperature and concentrationto transform its beryllium content into beryllium sulphate.

4. The process of extracting beryllium from beryl which comprisesmodifying the physical structure of the beryl by heating it at atemperature above 1000 C. and thereby increasing its reactivity withoutthe necessity of addition of reagents, rapidly cool ing the heated berylto fix it in its modified form, and thereafter treating the modifiedproduct with a reagent adapted to transform its beryllium content into asoluble form.

5. The process of extracting beryllium from beryl which comprisesmelting the beryl, rapidly cooling the melted material and thereaftertreating the same with a mineral acid of a temperature and concentrationto transform the beryllium content of the beryl into a soluble form.

6. The process of extracting beryllium from beryl which comprisesmelting the beryl, rapidly cooling the melted material and thereaftertreating the same with sulphuric acid of a temperature and concentrationto transform the beryllium content of the beryl into beryllium sulphate.

7. In a process of extracting beryllium from beryl, the step whichconsists in heating the beryl without the addition of reagents at atemperature above 1000 C. to change its physical structure and therebyincrease its reactivity to reagents.

8. In a process of extracting beryllium from beryl, the step whichconsists in melting the beryl.

9. In a process of extracting beryllium from beryl, the steps whichconsist in heating the beryl and rapidly cooling the same from itsheated state. 10. In a process of extracting beryllium from beryl, thesteps which consist in melting the beryl and rapidly cooling the samefrom its molten state.

11. The process of extracting beryllium from beryl, which comprisesmodifying the beryl by heating it sufiiciently, without the addition ofreagents, to cause the beryllium to become soluble in sulphuric acid,and treating the thus modified beryl with sulphuric acid of atemperature and concentration to form a solution containing beryllium.

12. The process of extracting beryllium and aluminum from beryl whichcomprises modifying the beryl by heating it sufficiently, without theaddition of reagents, to cause the beryllium and aluminum to becomesoluble in sulphuric acid, and treating the thus modified beryl withsulphuric acid of a temperature and concentration to form a solutioncontaining beryllium and aluminum.

13. The process of extractin beryllium from beryl, which comprisesIreating the beryl sufficiently, without the addition of reagents, tomodify it and thereby increase its reactivity to sulphuric acid andsubjecting it to a sulphuric acid solution of a concentration of 63 Baumor less and at a temperature suflicient to dissolve substantially all ofthe beryllium.

14. The process of extracting beryllium and aluminum from beryl whichcomprises modifying the physical structure of the beryl by heating it,without the addition of reagents, and treating the modified beryl with astrong mineral acld of a concentration and at a temperature to dissolvethe beryllium and aluminum and to leave the silica content of the berylinsoluble.

15. As a new and useful "product, beryl which has been heated at atemperature above 1000 C. and rapidly cooled and thereby had itsreactivity substantially increased.

16. As a new aiid useful product, beryl which has been heated to themelting point and rapidly cooled.

In testimony whereof we hereunto afiix our signatures.

CHARLES H. SAWYER. BENGT KJELLGREN,

CHARLES E. SAWYER. BENGT KJELLGREN- CERTIFICATE or CORRECTION.

Patent No. 1,823,864. Granted September 15, I931, to

CHARLES B. SAWYER ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 1,line 1, strike out "i have filed applications for this patent" andinsert instead We have filed applications; page 2, line 88, for"activity" read reactivity; page 3, line 100, for the misspelled word"washngs" read washings; page 4, line 77, for "An" read As; page '5,line 92, after "believe" insert a comma, page 6, line 100, for "84" read84; and that the said Letters Patent should be read with thesecorrections therein that the same may conform to the record of the casein the Patent Office.

Signed and sealed this 15th day of December, A. D. 1931.

M. J. Moore. (Seal) Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION.

Patent No. 1,823,864. Granted September 15, 1931, to

CHARLES B. SAWYER ET AL.

it is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 1,line 1, strike out "I have filed applications for this patent" andinsert instead We have filed appiications; page 2, line 88, for"activity" read reactivity; page 3, line 100, for the misspelled word"washngs" read washings; page 4, line 77, for "An" read As; page 5, line92, after "believe" insert a comma, page 6. line 100, for "84" read 84;and that the said Letters Patent should be read with these correctionstherein that the same may conform to the record of the case in thePatent Office.

Signed and sealed this l5th day of December, A. D. 1931.

M. J. Moore, (Seal) Acting Conunissioner of Patents.

